In an apparatus such as a video disk recorder (VDR) of the type recording information of high frequencies such as television signals, raised and recessed areas are formed in response to information to be recorded on a recording medium along a scanning path of a recording device.
In reproduction, the scanning path formed by the recording device must be precisely traced by means of a detecting device. For this purpose it is preferable to form grooves or ridges in the recording medium so as to guide the detecting device and also to define the areas or portions in which information are recorded.
Therefore there may be proposed a method in which a beam of predetermined energy level is always focused upon a recording medium having a plurality of photosensitive layers laminated thereupon so as to form a guide or guides thereupon and the beam which is modulated in response to information to be recorded is superimposed upon the first mentioned beam so as to record information in areas defined by the guides. However, there arises a problem that the compounds of the adjacent photosensitive layers mix or chemically react with each other in the boundary to produce new compounds so that the photosensitive layers are seriously degraded. Furthermore the recording media are subjected to aging.